Paget's disease of bone is a chronic progressive skeletal disorder of unknown etiology caused by an increase in bone remodeling (osteoclastic resorption and osteoblastic formation) leading to bone pain and skeletal deformities. The purpose of this study was to determine if administration of Zolendronate transdermally would cause therapeutic responses in at least 40% of patients with Paget's disease of bone as evidenced by a 50% reduction in bone resorption (dexoy pyridoline/creatinine and hydroxyproline/creatinine ratio) and bone formation (serum alkaline phosphatase and bone alkaline phosphatase levels). In this trial, two different concentrations, 2 mg/ml and 5 mg/ml in two different size transdermal systems, 10 cm2 and 25 cm2 were to be studied. M01RR000300683 The purpose of this study is to assess the safety and effectiveness of a testosterone 1% hydroalcoholic gel (T-gel) as a means to provide androgen replacement in hypogonadal men following its daily administration for six months. One hypothesis to be tested is that the gel preparation is as effective a form of androgen replacement as the currently available cutaneous patch. Previous studies have shown cutaneous patches to be a superior delivery system compared to intramuscular injections of testosterone. As part of the study, patients will be monitored for testosterone changes and other hormonal levels including gonadotropins, estradiol, dyhydrotestosterone, prolactin, as well as lipid profiles, blood chemistry and blood count. In addition, prostate evaluation will be performed by rectal examination and prostate specific antigen levels. Patients will have bone formation and resorption markers measured, and bone density studies will be performed. In addition, questionnaires will be filled out by the patients regarding mood and sexual function. Patients eligible for the study will be males between the ages of 18 and 65 years of age who have been diagnosed with testosterone deficiency requiring testosterone replacement. Most patients will be on androgen replacement and will have a wash-out period prior to protocol entry of at least six weeks for intramuscular testosterone injections and four weeks for transdermal or oral androgens. Patients will undergo a screening examination to validate their androgen deficiency syndrome and to confirm they meet critieria for protocol. Patients will be randomized to one of two doses of gel preparation, receiving either 50 or 100 mg T-gel or to a third group who will take the currently available transdermal testosterone patch. The duration of drug exposure will be 180 days and patients will be monitored on day 0, day 1, day 30, day 60, day 90, day 120, day 150 and day 180. On days 0, 1,30,90 and 180, patients will have blood drawn and minus3O, minusl5, 0, and 2,4,8,12 and 24 hours after application of the gel or patch. Days 60, 120 and 150 will be single am blood draws in the clinic. The study is ongoing and results and conclusions are not available at this time.